Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M17/00—Testing of vehicles
  • G01M17/007—Wheeled or endless-tracked vehicles
  • G01M17/0072—Wheeled or endless-tracked vehicles the wheels of the vehicle co-operating with rotatable rolls
  • G01M17/0074—Details, e.g. roller construction, vehicle restraining devices
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M17/00—Testing of vehicles
  • G01M17/007—Wheeled or endless-tracked vehicles
  • G01M17/0072—Wheeled or endless-tracked vehicles the wheels of the vehicle co-operating with rotatable rolls
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M13/00—Testing of machine parts
  • G01M13/02—Gearings; Transmission mechanisms
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M15/00—Testing of engines
  • G01M15/04—Testing internal-combustion engines
• • G—PHYSICS
  • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
  • G09B—EDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
  • G09B9/00—Simulators for teaching or training purposes
  • G09B9/02—Simulators for teaching or training purposes for teaching control of vehicles or other craft
  • G09B9/04—Simulators for teaching or training purposes for teaching control of vehicles or other craft for teaching control of land vehicles
  • G09B9/042—Simulators for teaching or training purposes for teaching control of vehicles or other craft for teaching control of land vehicles providing simulation in a real vehicle
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M15/00—Testing of engines
  • G01M15/04—Testing internal-combustion engines
  • G01M15/042—Testing internal-combustion engines by monitoring a single specific parameter not covered by groups G01M15/06 - G01M15/12
  • G01M15/048—Testing internal-combustion engines by monitoring a single specific parameter not covered by groups G01M15/06 - G01M15/12 by monitoring temperature

Definitions

• the subject invention relates to a method and a test stand for carrying out a test run on a test bench, wherein a test object in the form of the vehicle or a component of the vehicle is actually constructed and operated on the test stand and simulated simulation unit with a simulation model the test run.
• a test, experiment or experiment is an activity that serves to determine whether one (or more) technical component (s) (mechanical structure, hardware or software), generalized examinee, operates within certain framework conditions or whether certain properties exist ,
• the examinee is thus the technical system to be tested.
• the DUT may represent the entire system (e.g., a vehicle) or part of the overall system (e.g., an internal combustion engine, a propulsion system, an exhaust system, or an exhaust aftertreatment system of a vehicle, etc.).
• test benches adapted to the respective test specimen, such as an engine test bench, a powertrain test bench or a chassis dynamometer, are used for these activities. These test benches enable the test specimen to be systematically imprinted with certain ambient conditions, ie to be tested under these environmental conditions, and thus permit a repeatability of the test procedure. But they also serve to validate new or unknown processes in environments that would not be real or very time-consuming and costly for the candidate. Since a test environment can only incompletely correspond to the real environment, the results of the test must always be evaluated taking into account the quality of this test environment, ie the test bench and the simulated environment.
• Such virtual test drives can be generated with a wide variety of procedures, for example, they can be measured by real test drives or are also partly predefined or standardized (eg standardized consumption cycles). However, they can also be calculated using virtual environments in real time, or real-time (ie online), with a sufficient quality (so-called X-In-The-Loop test drive, where "X” stands for the test object, eg internal combustion engine, powertrain , etc.)
• X stands for the test object, eg internal combustion engine, powertrain , etc.
• various measurements can then be made during the virtual test drive, for which the test specimen to be examined (internal combustion engine, drive train, battery, vehicle, etc.
• a load unit such as a dynamometer (mechanical actuator) or a battery tester (electric actuator), loaded, which the test specimen is impressed by the mechanical test drive resulting mechanical or electrical load.
• a load unit such as a dynamometer (mechanical actuator) or a battery tester (electric actuator)
• Actuator such as a dynamometer (mechanical actuator) or a battery tester (electric actuator)
• These test drives on the test bench allow in particular developments or reviews perform on the test specimen on the test bench, without the Intelsyst em (eg a real complete vehicle), in which the examinee is normally involved as part of an overall system, to build and without the need to perform the test to be performed only with this real vehicle through a real test drive.
• such test bench tests have the advantage of a more reproducible and thus also a better comparability of the results.
• test bench can never reproduce the boundary conditions of a real test drive with absolute precision, but always with restrictions. However, it is not always desirable or necessary to subject the test specimen to these exact conditions. In some cases, one may only want to devise the candidate under hypothetical conditions.
• a thermal energy flow takes place via the surfaces of the named components and subcomponents.
• Another example provides the electrical energy storage of a hybrid vehicle. This component also interacts thermally with the environment / environment and is in turn influenced by ambient / environmental influences ("boundary conditions"), for example, the engine block or the exhaust system of a vehicle, depending on the boundary or ambient conditions, thermally different exchange with its environment.
• the cooling air blower often used on the test bench for generating an air flow over the test specimen, as well as the test bed conditioning (for example, the temperature of the test room space) are usually not sufficient to simulate the real environmental conditions on the test bench sufficiently accurate.
• the cooling air blowers are mainly used to map the effects on the engine cooling in terms of driving wind speed. These cooling fans are therefore often adequately dimensioned, or they do not offer the required degrees of freedom.
• the speed of the cooling air blower is often controlled only as a function of the driving speed.
• conditioning equipment for the media intake air, coolant, oil and charge air are also known on the test bench.
• the respective media temperature is influenced or regulated.
• the conditioning device for the intake air can continue to affect the humidity and the pressure.
• Both a cooling air blower, the test room air conditioning as well as the media conditioning get the setpoint specifications eg for temperature, humidity and pressure from the test bench automation.
• a specification in the form of a temporal course of the respective size (eg temperature) an interaction (in the sense of an X-in-the-loop simulation) takes place in the form of a reaction with a virtual environment of the test object, which is also An anticipated, future environment can not take place.
• there is the problem of reference value determination ie the determination of a default value, which allows a realistic mapping of the virtual environmental conditions of the test object.
• test stands in which test parts (such as a motor on a motor test bench) are thermally encapsulated in order to simulate the thermal boundary conditions better.
• test parts such as a motor on a motor test bench
• Such a structure can, for example, Krämer S., et al., "Relocation of role tests on the engine test bench", MTZ-Motortechnische Zeitschrift, 2015, 76 (3), pp 36-41 be taken
• the engine in a sealed engine enclosure and the exhaust line in a closed subfloor enclosure to simulate the thermal boundary conditions in the engine compartment or underbody, it is housed in an insulated housing (engine encapsulation, underfloor encapsulation) With the help of the fans, the temperature in the engine encapsulation and underbody encapsulation is controlled.
• This solution allows comparison of the results between emission measurements on the engine test bench and on the chassis dynamometer, but this is insufficient for a realistic picture of the ambient conditions one in the engine enclosure and the U
• a cooling system for a component such as an internal combustion engine, has become known from the patent DE 10 2013 213 863 B3, with which temperatures on the component can be adjusted by blowing the component with a blower matrix consisting of a plurality of individual blowers .
• the cooling system makes it possible to set different temperature zones (fields) on a component.
• a target temperature for individual points is specified as a setpoint, known from the outset (ie, already at the beginning of the test run), in the form of a time course, which is regulated by a control unit via the blower matrix, in order, e.g. to check the thermal resistance of the component or parts thereof.
• This is an improvement compared to conventional test rigs, especially with regard to the thermal boundary conditions for a bench test and possibly often sufficient.
• the component temperature as the target of the control on the test bench ignores the heat transfer processes in the form of the thermal energy flows of the real test object in the various test environments. Effects such as convection, heat radiation, etc., which play an important role in the components of the test object (real vehicle), are not taken into account on the test bench.
• the patent DE 10 2013 213 863 B3 is therefore based on the very restrictive assumption that the target temperatures at the selected measuring points are known as a function of time (i.e., can be predetermined in advance as reference variables of the control). These must be defined in advance, but with such an arbitrary determination no realistic environmental conditions can be generated, or they would have to be determined in advance in a real test drive, which in turn is very complex. The problem of reference value determination is not considered in the patent DE 10 2013 213 863 B3.
• test run for example in the form of a thermal X-In-The-Loop test drive, a test object on a test bench, and an associated test bench, which allow the test object to be selected.
• a test run for example in the form of a thermal X-In-The-Loop test drive, a test object on a test bench, and an associated test bench, which allow the test object to be selected.
• the test run to impose real environmental or environmental conditions or conditions, as they result from the laws of heat transfer of a virtual environment.
• thermal environmental conditions interact with the test specimen in the form of heat transfer processes and can be realistic (ie, actually occur in the future reality of the specimen as part of a real-life vehicle - eg, drive vehicle through Death Valley) or even only be fictitious (ie, conceived, but still real, physical conditions accordingly - example: vehicle drives through the Death Valley at an outside temperature of 60 ° C).
• the test object is also subjected to mechanical, electrical and / or mass and information currents (for example CAN communication) in addition to the thermal load.
• the thermal interaction of the test object or of the segment to be conditioned of the test object with the simulated environment can be reproduced as desired within certain technical limits.
• spatially and temporally variable heat transfer processes of the test specimen can be reproduced, which correspond to real conditions.
• these heat transfer processes can then be adjusted at the test stand on the test specimen, whereby the test specimen on the test bench is subjected to substantially the same, or the sufficiently similar, thermal conditions as a subcomponent of an overall system (eg a vehicle) during a test drive under real or fictive, but nevertheless physically equivalent conditions (example: drive from the thermal conditions Death Valley to the thermal conditions at the South Pole within two hours).
• the simulation quality can be increased if the simulation model additionally comprises one or more of the following models: vehicle model, driver model, road or distance model, wheel model, environment model.
• the simulation model additionally comprises one or more of the following models: vehicle model, driver model, road or distance model, wheel model, environment model.
• flexibility can also be increased with additional submodels, as this can take various influences into account in the test runs.
• At least one further measured variable of the test object is detected and processed in the simulation model. It is equally advantageous if, in addition, at least one further measured quantity of the test object environment of the test object is detected and processed in the simulation model.
• FIG. 1 shows a chassis dynamometer for a vehicle according to the prior art
• FIG. 6 shows the information flow in the implementation of the method according to the invention for operating a test bench.
• test object 2 is a vehicle and the test bench 1 is a chassis dynamometer.
• the device under test 2 could also be any subsystem of the vehicle, such as a powertrain, an internal combustion engine, a power pack, a turbocharger, a catalyst, etc.
• the test bench 1 a matching test stand, such as a Powertrain test bench, an engine test bench, a Powerpackprüf- stand, a turbocharger test, a catalyst test stand, etc.
• the test bed automation unit 3 can in particular also drive the test object 2.
• known driving robots could be arranged in the vehicle, which convert the control commands of the test bed automation unit 3, such as gearshifting, accelerating, etc.
• test bed automation unit 3 could also drive the test object 2 directly via a test object control unit, such as a vehicle control unit (ECU), a transmission control unit (TCU), a hybrid control unit, a battery management system, etc.
• a test object control unit such as a vehicle control unit (ECU), a transmission control unit (TCU), a hybrid control unit, a battery management system, etc.
• ECU vehicle control unit
• TCU transmission control unit
• hybrid control unit a battery management system
• the test bed automation unit 3 could, for example, control the throttle valve position ⁇ (see FIG. 3) or the fuel injection.
• the test object 2 is loaded by a loading machine (generally actuator) 5, in the present case mechanically (mechanical power flow between the test object and the surroundings).
• a loading machine generally actuator
• the (mechanical) loading machine 5 is the drive or output of the bench rolls, as indicated in FIG.
• the mechanical loading machine 5 would be e.g. a dynamometer or an electric dynamometer, which is connected to the internal combustion engine or the drive train.
• the loading machine 5 would be electrical, e.g. in the form of an electric battery tester. Suitable loading machines for various specimens 2 are well known, which is why will not be discussed here in detail.
• the loading machine 5 is usually controlled by an actuator controller 4, which in turn receives setpoints from the test bed automation unit 3, to control, for example, certain, frequently transient, load moments M or certain, frequently transient, speeds n on the test piece 2.
• a torque measuring device 6 and / or a speed measuring device 7 are usually provided on the test bench 1, which measure the corresponding actual values of the load moment M and the rotational speed n of the test object 2 and make it available to the test bed automation unit 3.
• other or additional measured variables such as, for example, an electrical current or an electrical voltage, can also be measured and supplied to the test stand automation unit 3 for other test objects 2 or test bench types.
• an emission measurement is carried out, for example, with an exhaust gas measuring system 14.
• an exhaust gas measuring system 14 is carried out, for example, depending on the test specimen 2, other or additional, especially for the development of the specimen required measurements could be made, such as a consumption measurement, measurement of electrical energy flow, etc.
• At the test stand 1, at least one conditioning unit 16 is also often provided for conditioning the test piece environment of the test piece 2 and / or the test piece 2.
• this allows the specimen 2 to be impressed with a certain (for example a desired) spatially and temporally variable heat transfer, which the specimen 2 on the test bench 1 exchanges with its specimen environment.
• the heat transfer may be coupled to a certain mass transfer, e.g. a heat transfer with an air stream or other stream.
• the heat transfer thus also includes such mass transfers as equivalents to a heat transfer.
• a conditioning air conditioner for adjusting the ambient temperature, humidity, etc. of the DUT environment is provided as the conditioning unit 16.
• the conditioning unit 16 may also include a blower 8 for simulating, for example, a wind.
• the blower 8 can also be realized separately from the conditioning unit 16 as a separate device on the test bench 1. Such a fan 8 provides a contribution to impressing the specimen 2 with a certain (e.g., a desired) generally spatially and temporally variable heat transfer process that the specimen 2 exchanges with the specimen environment.
• a certain (e.g., a desired) generally spatially and temporally variable heat transfer process that the specimen 2 exchanges with the specimen environment.
• various conditioning units 16 can often be used for different types of test stands.
• the conditioning unit 16 comprises a blower 8, which impresses a specific air flow field 9 on the test piece 2.
• conditioning unit 16 on the test stand 1 for conditioning the test piece 2 can also comprise a media conditioning unit, for example an intake air conditioning, charge air conditioning, oil conditioning or cooling water conditioning, which are not shown in FIG. 1 for reasons of clarity.
• media conditioning unit for example an intake air conditioning, charge air conditioning, oil conditioning or cooling water conditioning, which are not shown in FIG. 1 for reasons of clarity.
• the conditioning unit 16 optionally with blower 8 and / or with media conditioning unit, usually receive from the test bed automation unit 3 certain set values (temperatures, air humidities, mass flows,...) That are supplied by the conditioning unit 16 or the blower 8 or the media conditioning unit.
• certain set values temperatures, air humidities, mass flows, etc.
• the desired (eg realistic) heat transfer processes on the test piece 2 or on test piece components can not be reproduced inadequately or - in view of the test task to be performed.
• the thermal conditions of the test object 2 are reproduced in accordance with these specifications, which will be described below with reference to FIG.2 using the example of a chassis dynamometer as a test bench 1 and a vehicle as a test object 2 and with reference to FIG Test stand 1 and an internal combustion engine as test specimen 2. In this case, for reasons of clarity, not all components of the test stand 1 are shown as described for FIG.
• a scholarlingskom- component PKi may also be a component of the DUT 2 or part of an assembly of the DUT 2, for example, an exhaust pipe section of the exhaust line 1.
• a specimen component PKi is in particular a part of the specimen 2 to which a spatially and temporally variable thermal interaction (heat transfer, heat flux densities) is to be impressed, which the specimen 2 exchanges with its specimen environment, as described below.
• parts of the specimen 2 whose behavior or properties depend on a thermal load are suitable as specimen components PKi. This can be influenced on certain properties of the DUT 2. For example, the property "NOx emissions” depends, among other things, on the thermal load of the sample component "catalyst".
• different measuring units MEi can also be provided for measuring different measured quantities MGi.
• at least one measured variable MGi is a temperature, or a measured variable, from which a temperature can be calculated or estimated.
• at least one measuring unit MEi is for example a simple temperature sensor with which a temperature of the test piece 2 at the measuring point MSi is measured.
• a measuring unit MEi for detecting a temperature may, for example, be a medium-temperature temperature, such as an exhaust gas temperature or a fluid temperature, an assembly or component temperature or a surface temperature.
• a medium-temperature temperature such as an exhaust gas temperature or a fluid temperature, an assembly or component temperature or a surface temperature.
• thermal imaging cameras as measuring unit MEi, or with other methods, it is also possible to measure complex three-dimensional temperature fields of the test object 2, of a test object component PKi, or of a part thereof.
• measuring units MEi can additionally be used to measure a media flow, such as an exhaust gas flow through the exhaust gas line 11 or an intake air flow. It could also be media pressures, such as exhaust pressures, measured at different locations.
• a measured variable MGi of the test piece environment of the test piece 2 preferably in the vicinity of the test piece 2 can additionally be measured.
• a measured variable MGi of the test object environment may be, for example, the air pressure, an ambient temperature, a humidity, etc.
• heat flow Q which also equivalently means a heat flux density q, or any other equivalent to a heat flow Q size.
• a heat flow actuator ' ⁇ 5 ⁇ may be a heat sink, a heat source, or both.
• the heat (no matter in which direction) to transmit or in particular the striglingskomponenten PKi heat flows Q can impress.
• Conceivable for example, water or air heat exchangers, fluid feeders (eg blowers, venturi), Peltier elements, spray nozzles for spraying with liquids such as water, etc.
• a conventional conditioning unit 16 for scholarstandraumkondition ist basically as a heat flow actuator 15 j used as indicated in Fig.2 and 3.
• a blower 8 of the test stand 1 or stipulatekonditionierijn the condition- can purity 16, for example a Intake air, a charge air conditioning, an oil conditioning or cooling water conditioning of an internal combustion engine 10, as are used jacketstromaktuator ⁇ 5 i, as shown in Figure 3 with the heat flow actuators ⁇ 5 ' ⁇ , 15 2 and 15 3 indicated.
• Such a media conditioning unit is typically designed as a heat exchanger for the respective medium.
• the specimen 2 or a sketchlingskomponente PKi by means of a politicians ⁇ 5 i on the heat flow Q a certain, preferably a predetermined, spatially and temporally variable heat transfer impressed, which exchanged the DUT 2 with its DUT ambient.
• the exact execution of the toppingstromaktuatoren ⁇ 5 i is incidental to the invention.
• the only necessary requirement for the heat flow actuator ⁇ i is to be able to memorize a heat flow Q to a test piece component PKi of the test piece 2 and / or a heat flow Q away from a test piece component PKi of the test piece 2, or both.
• Each heat flow actuator ⁇ 5 i can therefore supply heat to the test specimen 2 and / or dissipate it.
• a measure of a baling stromaktuators ⁇ 5 can be i ER words, such as fan speed or a flow velocity of the air when the toppingstromaktuator ⁇ 5 i is a blower 8 (as shown in Figure 2 with the measuring unit MEn), or a fluid flow of a heat exchange fluid (air, water, etc.) when the heat flow actuator 15 j is a heat exchanger.
• the control of the heat flow actuators ⁇ 5 i mestromes for setting a desired heat Q accepts at least one heat flow controller 17.
• Heat flow regulator 17 may be a separate entity on the test stand 1 (as in Figure 3), and / or integrated into the slaughterstromaktuator ⁇ 5 i, and / or as part of the test automation unit 3 (as in Figure 2) done.
• the regulation of the heat flow actuators' ⁇ 5 ⁇ by heat flow controller (s) 17 is accordingly a multivariable control, which to memorize at least one measuring sizes MGi, in particular at least a temperature at a measuring point MSi on the test piece 2, processed with the goal of a particular heat flux Q. If gate 15 j also a measuring unit MEi is required for detecting an actual value for the regulation of a dressedstromaktua-, a corresponding measuring unit MEi is provided.
• the required actual size can also be calculated from other measured variables MGi.
• the heat flow controller 17 may be implemented any suitable control law, wherein it does not depend on the specific implementation of the control law in the invention.
• the measuring units MEi deliver their measured quantities MGi to the heat flow regulators 17, which process the corresponding measured variable MGi, and optionally also to the test bench automation unit 3 or to a simulation unit 20.
• the politiciansstromaktuatoren ⁇ 5 i generate on the DUT 2 together a temporally and spatially variable heat flow field Q f , or analogous to a heat flow density field q f , which acts on theticianlingskomponenten PKi.
• Q f Q 1, ..., Q J]
• a segment Si may be a whole sample component PKi, for example the exhaust gas line 1 1 or an exhaust gas aftertreatment unit 12, 13 of the exhaust line 1 1.
• the segments Si can be divided just as finely, for example, a device under test component PKi can be divided into several segments Si, for example, the exhaust line 1 1 can be divided into ten segments Si.
• an entire test object 2 such as a battery
• an entire test object 2 such as a battery
• Q Si ie a heat flow from the DUT ambient into the respective segment Si or from the respective segment Si into the DUT environment.
• the heat flow actuators ⁇ i 5 generate heat flows Q j, either the sketchlingskomponente PKi towards and / or away from.
• measuring units MEi are provided on the test piece 2 and possibly also in the surroundings of the test piece 2 at intended measuring points MSi, at least one temperature being measured on the test piece 2.
• the measuring units MEi can measure MGi of the DUT 2 or a beaulingskomponenten PKi, but also measures MGi the DUT environment of the DUT 2, such as air pressure or humidity in the test room, or measures MGi a dressedstromaktuators ⁇ 5 i , such as a flow velocity, be recorded.
• the measured variables MGi detected by the measuring units MEi are fed to the heat flow controller 17, which now, according to the implemented control law, sets the manipulated variables for the
• this simulation unit 20 On the basis of at least one suitable "real-time-capable" simulation model 22, this simulation unit 20 generates the desired values in the form of the segment heat flows Q Si , which are set by the temporally and spatially variable heat flow field Q f .
• the simulation model 22 thus, for example, moves a virtual vehicle through a virtual world.
• the simulation unit 20 can also be implemented in the test bench automation unit 3.
• the simulation is carried out for the virtual test drive on the test bench 1, preferably in real time. That is, for each time step, for example, in the millisecond to minute range, a current setpoint specification is calculated to impose the required heat flow fields Q f using the townlestromaktuator ⁇ 5 i .
• the simulation model 22 comprises at least one thermal simulation model 23, as illustrated in FIGS.
• the thermal simulation model 23 thus forms in particular the thermal behavior of vehicle components that are not actually present at the test stand 1 (possibly also components installed on the test stand) and the environment (air flow, road surface, eg in the form of engine compartment and underbody models ").
• a vehicle model 24, a driver model 25, a road or track model 26, a wheel model 27, etc. may also be implemented, as exemplified in FIG.
• an environment model can be provided which simulates the environment of the vehicle.
• the various submodels of the simulation model 22 work together to implement the test run taking into account the thermal interaction of the test specimen 2 with the surroundings of the vehicle.
• other influences such as different drivers (conservative, aggressive, etc.), road conditions (eg aquaplaning, ice, various road surfaces, etc.) or different tires can be mapped.
• the Constant terrain heat flow Q f Field results from a simulated driving situation taking into account certain environmental conditions.
• a sporty driver cuts a curve and drives over an ice plate or drives through a puddle (eg splashing water), whereas a conservative driver drives out the curve and thus bypasses the ice plate or the puddle.
• This has a direct influence on the heat transfer processes on the DUT 2.
• real controls of a vehicle such as a steering wheel, an accelerator pedal, a brake pedal, a gear shift, are actively intervened in the test run can.
• the simulation is preferably carried out in real time in the required temporal resolution.
• test run can also be predetermined in another way, for example in Form of a conventional time-based or path-based speed specification.
• the concrete test run is determined by the partial models or the time-based or path-based speed specification, the thermal interaction of the test object 2 with the environment occurring in each case being simulated by the thermal simulation model 23.
• the simulation unit 20 further has an interface 21 (FIG. 5), via which the simulation model 22 required measured variables MGi, but also actual variables of the test object 2, such as one or more actual rotational speeds n , x , or the loading machine 5, such as one or more Actual torques M ist, z , can be supplied and via the calculated by the simulation model 22 setpoints for controlling the DUT 2 (eg throttle position a so n) and / or the test bench 1 (eg, a target torque M soN and / or a target speed n so n the loading machine 5 or more target torques and / or set speeds for multiple loading machines), or the test run, in particular the heat flow actuators 15 j , are output.
• the simulation model 22 required measured variables MGi, but also actual variables of the test object 2, such as one or more actual rotational speeds n , x , or the loading machine 5, such as one or more Actual torques M ist, z , can be supplied and via the calculated by the simulation model 22 setpoints for controlling
• the interface 21 also provides necessary signal conditioning mechanisms, eg filters for the measured quantities MGi.
• necessary signal conditioning mechanisms eg filters for the measured quantities MGi.
• the thermal simulation model 23 which simulates the thermal interaction of a device component PKi with the environment, can have any structure, for example in the form of a physical model, an empirical model or a trained model (neural network, linear model network, etc.). Furthermore, the thermal simulation model 23 can simulate the behavior of a test object component PKi to be examined and actually present on the test bench 1 in order to reconstruct, for example, unmeasured or measurable variables (eg temperatures) (eg by means of a control-related observer). In each predetermined time step, the thermal simulation model 23 determines setpoint values for the segment heat flows Q Si for at least one segment Si, preferably for each segment Si of the test object 2.
• the thermal simulation model 23 processes at least one measuring point MSi belonging to a measuring unit MEi measured temperature (or an equivalent physical quantity).
• the thermal simulation model 23 can also process further measured variables MGi, such as mass or volume flows, air pressure, ambient temperature, etc. Which measured quantities MGi are required depends on the respective implementation of the thermal simulation model 23 and, if appropriate, on the respective implementation of the other models of the simulation model 22. In this case, it is also possible to measure measured variables MGi needed for the thermal simulation model 23 not directly, but instead Estimate the basis of other, measured measures MGi, for example by means of a suitable observer, or to calculate.
• an exhaust line 1 1 it is possible, for example, from a measurement of an inlet and outlet temperature of the exhaust gas into and out of the exhaust line 1 1 and a measurement of the exhaust gas mass flow through the exhaust line 1 1 to calculate the surface temperature at different points of the exhaust line 1 1.
• the thermal simulation model 23 can also process variables of the test run itself, for example obtained from other models of the simulation model 22 or from the speed specification, eg a vehicle speed.
• ambient conditions such as air temperature, air humidity, etc.
• events such as, for example, a thunderstorm, holding phases of the vehicle or the passage through a puddle, which can likewise be incorporated into the thermal simulation model 23.
• the setpoint values of the segment heat flows Q si determined for example numerically or model-based, are transferred to a heat flow regulator 17, which supplies them
• the test object 2 is moved as part of a real test drive embedded in a real vehicle on a real proving ground. Then certain real segment heat flows Q si would result for the segments Si defined on the test specimen 2.
• the task now is to generate these real segment heat flows Q si that occur in the real test drive in a virtual test drive on the test bench 1, ie in a test run, as setpoints from a suitable thermal simulation model 23. According to the laws of physics, these segment heat flows Q si are decisively dependent on the temperature fields resulting on test specimen 2, which are approximately detected via the measuring points MSi, for example via heat conduction, convection, thermal radiation.
• the temperatures of the specimen 2 are measured at n measuring points MSi and calculated on the basis of the thermal simulation model 23 for the i segments Si, the segment heat flows Q si and adjusted with a heat flow controller 17 and the heat flow actuators 15j on the test bench 1.
• measuring points MSi there is no need for 1 ⁇ correspondence between measuring points MSi and segments Si.
• On individual segments Si it is possible, for example, to measure the temperature several times, but on other segments Si no temperature measurement is necessary at all. There, the temperature field is then just estimated.
• the information flow for regulating the segment heat flows Q si is again shown in a generalized manner in FIG.
• measured quantities MGi such as variables of the environment (ambient temperature, humidity, air pressure, etc.) and also mass or volume flows can be measured, as explained above.
• the measured quantities MGi are fed via the interface 21 to the thermal simulation model 23 of the simulation model 22 in the simulation unit 20, and possibly also to other models of the simulation model 22.
• the thermal simulation model 23 determines the nominal values of the segment heat flows Q si at the segments Si from the measured variables MGi.
• These target values of the segment-heat flows Q si be a heat flow regulator 17 to pass over the i for regulating heat flow actuators ⁇ . 5
• the heat flow actuators ⁇ 5 i generate the required heat flows Qj, which act on the test object components PKi to be conditioned or on the segments Si.
• the segment heat flows Q si change very rapidly in successive time steps, for example when passing through a puddle, where, for example, a lot of puddle water evaporates at the hot muffler of the exhaust line 1 1 in the short term, it may be that the heat flow actuator ⁇ 5 i due to always limited dynamics is not able to regulate such rapid changes in the segment heat flows Q si . In this case it can be provided that at least the segment heat flows Q si in the integral
• the simulation unit 20 can also exchange information with the test bed automation unit 3 and / or the actuator controller 4.
• the entire vehicle can also be considered as the vehicle component
• the thermal interaction of the test specimen 2 with the surroundings in the form of heat transfer processes which the test specimen 2 would experience in a real vehicle during a real test drive simulated.
• any other, in particular fictitious, heat transfer processes can also be specified and used in the course of a test run.
• the heat transfer processes resulting from this simulation are adjusted at the test bench i 1 with heat flow actuators ⁇ 5th In this way, very realistic testing runs on the test bench 1.

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